<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    let students = [
      { name: '小明', age: 18, gender: '男', hometown: '河北省' },
      { name: '小红', age: 19, gender: '女', hometown: '河南省' },
      { name: '小刚', age: 17, gender: '男', hometown: '山西省' },
      { name: '小丽', age: 18, gender: '女', hometown: '山东省' }
    ]
    // for (let i = 0; i < students.length; i++) {
    //   // console.log(i)  // 下标索引号
    //   // console.log(students[i]) // 每个对象
    //   // console.log(students[i].name)
    //   // console.log(students[i].age)
    //   // console.log(students[i].gender)
    //   // console.log(students[i].hometown)
    //   // console.log('-------')
    //   let obj = students[i]
    //   for(let k in obj){
    //     document.write(obj[k])
    //   }
    //   document.write('<br>')
    // }
    // students[0].age = 20
    // Array.prototype.customProp = "test";
    // for (let k in students) {
    //   console.log(students[k].age)
    //   console.log(students[k].name)
    //   console.log(students[k].gender)
    //   console.log(students[k].hometown)
    // }


  </script>
</body>

</html>